1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
|
; RUN: opt -objc-arc-contract -S < %s | FileCheck %s
target datalayout = "e-p:64:64:64"
declare i8* @objc_retain(i8*)
declare void @objc_release(i8*)
declare void @use_pointer(i8*)
@x = external global i8*
; CHECK: define void @test0(
; CHECK: entry:
; CHECK-NEXT: tail call void @objc_storeStrong(i8** @x, i8* %p) nounwind
; CHECK-NEXT: ret void
define void @test0(i8* %p) {
entry:
%0 = tail call i8* @objc_retain(i8* %p) nounwind
%tmp = load i8** @x, align 8
store i8* %0, i8** @x, align 8
tail call void @objc_release(i8* %tmp) nounwind
ret void
}
; Don't do this if the load is volatile.
; CHECK: define void @test1(i8* %p) {
; CHECK-NEXT: entry:
; CHECK-NEXT: %0 = tail call i8* @objc_retain(i8* %p) nounwind
; CHECK-NEXT: %tmp = load volatile i8** @x, align 8
; CHECK-NEXT: store i8* %0, i8** @x, align 8
; CHECK-NEXT: tail call void @objc_release(i8* %tmp) nounwind
; CHECK-NEXT: ret void
; CHECK-NEXT: }
define void @test1(i8* %p) {
entry:
%0 = tail call i8* @objc_retain(i8* %p) nounwind
%tmp = load volatile i8** @x, align 8
store i8* %0, i8** @x, align 8
tail call void @objc_release(i8* %tmp) nounwind
ret void
}
; Don't do this if the store is volatile.
; CHECK: define void @test2(i8* %p) {
; CHECK-NEXT: entry:
; CHECK-NEXT: %0 = tail call i8* @objc_retain(i8* %p) nounwind
; CHECK-NEXT: %tmp = load i8** @x, align 8
; CHECK-NEXT: store volatile i8* %0, i8** @x, align 8
; CHECK-NEXT: tail call void @objc_release(i8* %tmp) nounwind
; CHECK-NEXT: ret void
; CHECK-NEXT: }
define void @test2(i8* %p) {
entry:
%0 = tail call i8* @objc_retain(i8* %p) nounwind
%tmp = load i8** @x, align 8
store volatile i8* %0, i8** @x, align 8
tail call void @objc_release(i8* %tmp) nounwind
ret void
}
; Don't do this if there's a use of the old pointer value between the store
; and the release.
; CHECK: define void @test3(i8* %newValue) {
; CHECK-NEXT: entry:
; CHECK-NEXT: %x0 = tail call i8* @objc_retain(i8* %newValue) nounwind
; CHECK-NEXT: %x1 = load i8** @x, align 8
; CHECK-NEXT: store i8* %x0, i8** @x, align 8
; CHECK-NEXT: tail call void @use_pointer(i8* %x1), !clang.arc.no_objc_arc_exceptions !0
; CHECK-NEXT: tail call void @objc_release(i8* %x1) nounwind, !clang.imprecise_release !0
; CHECK-NEXT: ret void
; CHECK-NEXT: }
define void @test3(i8* %newValue) {
entry:
%x0 = tail call i8* @objc_retain(i8* %newValue) nounwind
%x1 = load i8** @x, align 8
store i8* %newValue, i8** @x, align 8
tail call void @use_pointer(i8* %x1), !clang.arc.no_objc_arc_exceptions !0
tail call void @objc_release(i8* %x1) nounwind, !clang.imprecise_release !0
ret void
}
; Like test3, but with an icmp use instead of a call, for good measure.
; CHECK: define i1 @test4(i8* %newValue, i8* %foo) {
; CHECK-NEXT: entry:
; CHECK-NEXT: %x0 = tail call i8* @objc_retain(i8* %newValue) nounwind
; CHECK-NEXT: %x1 = load i8** @x, align 8
; CHECK-NEXT: store i8* %x0, i8** @x, align 8
; CHECK-NEXT: %t = icmp eq i8* %x1, %foo
; CHECK-NEXT: tail call void @objc_release(i8* %x1) nounwind, !clang.imprecise_release !0
; CHECK-NEXT: ret i1 %t
; CHECK-NEXT: }
define i1 @test4(i8* %newValue, i8* %foo) {
entry:
%x0 = tail call i8* @objc_retain(i8* %newValue) nounwind
%x1 = load i8** @x, align 8
store i8* %newValue, i8** @x, align 8
%t = icmp eq i8* %x1, %foo
tail call void @objc_release(i8* %x1) nounwind, !clang.imprecise_release !0
ret i1 %t
}
; Do form an objc_storeStrong here, because the use is before the store.
; CHECK: define i1 @test5(i8* %newValue, i8* %foo) {
; CHECK: %t = icmp eq i8* %x1, %foo
; CHECK: tail call void @objc_storeStrong(i8** @x, i8* %newValue) nounwind
define i1 @test5(i8* %newValue, i8* %foo) {
entry:
%x0 = tail call i8* @objc_retain(i8* %newValue) nounwind
%x1 = load i8** @x, align 8
%t = icmp eq i8* %x1, %foo
store i8* %newValue, i8** @x, align 8
tail call void @objc_release(i8* %x1) nounwind, !clang.imprecise_release !0
ret i1 %t
}
; Like test5, but the release is before the store.
; CHECK: define i1 @test6(i8* %newValue, i8* %foo) {
; CHECK: %t = icmp eq i8* %x1, %foo
; CHECK: tail call void @objc_storeStrong(i8** @x, i8* %newValue) nounwind
define i1 @test6(i8* %newValue, i8* %foo) {
entry:
%x0 = tail call i8* @objc_retain(i8* %newValue) nounwind
%x1 = load i8** @x, align 8
tail call void @objc_release(i8* %x1) nounwind, !clang.imprecise_release !0
%t = icmp eq i8* %x1, %foo
store i8* %newValue, i8** @x, align 8
ret i1 %t
}
!0 = metadata !{}
|